1. Field of the Invention
The present invention relates to noise-damping composites of the type which include outer metal layers and an intermediate viscoelastic layer for sound and vibration damping characteristics. In particular, the invention relates to a method of forming such composites.
2. Description of the Prior Art
Composites with a viscoelastic layer between two metal layers have been used to attenuate noise and vibration in a number of different environments where noise is a problem, especially to diminish the propagation of structural noise and the transmission of air-borne noise. In certain applications, such as in the head arms of computer disk drives, it is desirable that the viscoelastic layer be very thin. However, the viscoelastic material not only produces sound dampening, but is also the adhesive which holds the two outer metal skins together. It is extremely difficult to apply very thin viscoelastic layers, having a thickness of a fraction of a mil., in a continuous manner.